— 618 —
Our Knowledge of our own Existence is intuitive.
      §3. As for our own Existence, we perceive it so plainly, and so cer-
tainly, that it neither needs, nor is capable of any proof. For nothing
can be more evident to us, than our own Existence. I think, I
reason, I feel Pleasure and Pain; Can any of these be more evident to
me, than my own Existence? If I doubt of all other Things, that very
doubt makes me perceive my own Existence, and will not suffer me
to doubt of that. For if I know I feel Pain, it is evident, I have as
certain a Perception of my own Existence, as of the Existence of the
Pain I feel: Or if I know I doubt, I have as certain a Perception of the
Existence of the thing doubting, as of that Thought, which I call
doubt. Experience then convinces us, that we have an intuitive Know-
ledge of our own Existence, and an internal infallible Perception that
— 619 —
we are. In every Act of Sensation, Reasoning, or Thinking, we are
conscious to our selves of our own Being; and, in this Matter, come
not short of the highest degree of Certainty.
Locke Hum IV, 9, §3, pp. 618-619